If you tasted Indian cuisine, you most likely encountered yellow spice, called turmeric. Its bright yellow color is due to curcumin, a chemical produced by some plants of the ginger family. While it has been known and used in Ayurvedic medicine for centuries, turmeric, and its derivative curcumin just recently gained popularity as a potent health supplement in the Western hemisphere. With increased interest from the naturopathic community, there are more and more claims about what curcumin can cure.
Multiple human clinical trials demonstrated the effectiveness of curcumin and its byproducts against oxidative stress, inflammation, pain, diabetes, and colorectal cancer.
Unfortunately, we do not have any clinical studies specifically designed to show the effect of the curcumin on the bladder and its value for preventing or curing urinary tract infections (UTIs) or interstitial cystitis (IC). However, there are results of two clinical studies that confirmed the positive effect of curcumin on kidney function (one among diabetics and another among lupus patients).
Many studies that looked at antibacterial properties of curcumin did so in a lab setting (in vitro) or in animals. This makes any health claims much less relevant in regards to human health.
Why lab experiments are not enough
A lab study is rarely capable of replicating how a chemical would work in the human body.
For example, curcumin’s antimicrobial activity shows promise when analyzed in a lab setting. This means that bacteria were grown on a Petrie dish, a researcher added curcumin to the dish, and some bacteria did not survive. However, this doesn’t mean that if your UTI is caused by the same bacteria, curcumin can help to treat the infection in the bladder. There are several reasons why.
First, curcumin has to pass through the digestive tract and is later metabolized by the liver. The results of this process (curcumin metabolites) are chemically different from the original compound.
Second, these compounds have to reach the bladder in significant concentration in order to have an antibacterial effect (this is how antibiotics work, for example). The best way to know if this happens is to analyze the urine of people who take a large amount of curcumin. Indeed, when taken orally, an only negligible amount of curcumin metabolites reaches the bladder or can be detected in blood, while most of the curcumin and its metabolites are evacuated with poop.
Bottom line, curcumin has a very poor oral bioavailability: you absorb little of what you swallow and, basically, curcumin just passes through your digestive tract in a form of its metabolites.
“The poor bioavailability is still one of the major problems facing the use of curcumin despite its reported benefits, which appear to be primarily due to poor absorption, rapid metabolism, and rapid excretion. An oral dose of 1,000 mg/kg of curcumin administered to rats resulted in approximately 75% of the dose being excreted in feces, and negligible amounts were detected in the urine,”- https://www.ncbi.nlm.nih.gov/pubmed/17999464.
“Sharma et al administered Curcuma extract 440 to 2,200 mg/day (36 to 180 mg of curcumin) for up to 29 days to patients with advanced colorectal cancer and failed to detect curcumin or its metabolites in blood or urine. Neither curcumin nor its metabolites were detected in blood or urine, but curcumin was recovered from feces. The results suggest that (a) Curcuma extract can be administered safely to patients at doses of up to 2.2 g daily, equivalent to 180 mg of curcumin; (b) curcumin has low oral bioavailability in humans and may undergo intestinal metabolism, and (c) larger clinical trials of Curcuma extract are merited,” – https://www.ncbi.nlm.nih.gov/pubmed/11448902/.
Instead, curcumin affects gut microbiome!
Given its poor bioavailability, how is it possible that several clinical studies demonstrated curcumin’s effectiveness to lower inflammation rates and even improve chances in beating colon cancer? The answer could be again, in its poor bioavailability. Instead of being absorbed in your blood or released in your urine, curcumin metabolites reach peak levels in your lower gut and colon, affecting your gut microbiome.
“The administration of curcumin significantly shifted the ratio between beneficial and pathogenic microbiota by increasing the abundance of bifidobacteria, lactobacilli, and butyrate-producing bacteria and reducing loads of Prevotellaceae, Coriobacterales, enterobacteria, and enterococci. These alterations in gut microbiota could explain the immune modulation and antihyperlipidemic efficacy of curcumin aside from its anti-inflammatory and anticolonotropic carcinogenicity activity,”– https://www.ncbi.nlm.nih.gov/pubmed/17999464
Therefore, the most important curcumin’s effect on the body is to drastically shift gut microbiome toward beneficial bacteria. We can speculate, that this change in gut microbiome triggers a domino-effect that gradually delivers systemic health benefits. With this fact in mind, you can think of curcumin as a potent prebiotic that helps you maintain healthy gut flora and supports your overall health. Of course, some bi-products of curcumin also can have strong local antiseptic, anti-inflammatory, and anti-cancer activity, important in regards to colon health.
Can turmeric or curcumin help with UTI?
Curcumin cannot help with an acute infection. Since turmeric (and its derivative curcumin) are not going to show up in your urine, they can not directly affect anything that happens in your bladder. So if you are experiencing UTI symptoms, there is no need to waste your time on curcumin. Try other OTC UTI options.
However, as long as we agree that the best way to cure chronic recurrent (not acute!) UTIs is to fix gut dysbiosis, then sure, curcumin can truly help shift your gut microbiome into the right direction. Especially if you are not that great at following a good diet.
To improve the results make sure to take the right probiotics and add some other prebiotics, too. Any kind of insoluble fiber works great, but variety is a key.
Another study that is worthy of mentioning in the context of chronic UTI administered a combination of Hyaluronic Acid, Chondroitin Sulfate, Curcumin, and Quercetin to 98 female volunteers (prone to frequent UTIs), for a period of 6 months. The study demonstrated a positive impact of this combo on almost all key parameters (less recurrent UTIs, less frequency and pain etc.). It’s hard to say, what role every element of this supplementation regime played in the positive effect, plus the study wasn’t placebo-controlled, so we don’t know how the results could compare to a “sugar-pill” group. Theoretically, however, the choice of supplements could have helped restore GAG-bladder layer and, perhaps, curcumin helped increase the number of beneficial Lactobacilli.
The Joint FAO/WHO Expert Committee on Food Additives listed curcumin as Generally Recognized As Safe (GRAS) with an acceptable daily intake level of 0.1–3 mg/kg of body weight.
“Lao et al. studied the safety of curcumin in 24 healthy volunteers using curcumin capsules with single escalating doses from 500 mg to 12,000 mg. Seven patients developed some first-grade adverse effects, including headaches, rashes, diarrhea, and yellowish stools. Subjects took the dose with 8 fl. oz. of water followed by a standard meal containing dietary fat (providing 34 g or 42 g fat, per 2200 kcal/day or 2500 kcal/day meal plan, respectively),”– https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1434783/.
Also, it is widely recommended to pair curcumin with piperine (a black pepper extract) or with fatty food and oil. This helps your body to absorb more curcumin instead of just pushing it through. To supplement curcumin with piperine, take 500 mg of the former with 20 mg of the latter, thrice a day (i.e., 1,500 mg of curcumin and 60 mg of piperine per day).
However, as discussed earlier, taking curcumin “as is” could be your best bet if you’d like to shift your gut microbiome.